A conventional spark plug includes an insulator core assembly and an outer shell having a hexagonal mounting section. A firing center electrode extends from the insulator core assembly and a ground electrode extends from the outer shell, with the electrodes being positioned to define a spark gap. When the spark plug is mounted in an engine, the spark gap is located in the combustion chamber of the engine.
The spark plug is installed in the head of a combustion engine by inserting the spark plug in a spark plug well of the head and then installing the spark plug in a threaded channel opening into the combustion chamber. The spark plug is tightened into the threaded channel by using, for example, a hexagonal socket placed around the hexagonal mounting section of the outer shell of the spark plug. The socket is positioned over the spark plug and surrounds the upper portion of the spark plug. The spark plug well has a larger diameter than the outer diameter of the socket so that the socket can be inserted into the spark plug well.